Vacuum cylinder for pulp and paper mills



Essa 19 H. B. TOHMS Vacuum CYLINDER FOR PULP AND PAPER iMlLLs.

3 SHEETS'SHEET I Fl LED JUNE 30. 1919 Z ZZZ/67% JZ/U y Z5 172/5 1,439,493 H. 8, TOHMS. VACUUM CYLINDER FOR PULP AND PAPER MILLs. I FILED JUNE 30. I919, -3 SHEETS'SHEET 2 8 88 9 @m; 119 @220 mgw H. B, TOHMS. VACUUM CYLINDER FOR PULP AND PAPER Mums.

FILED JUNE 30- 19\9. 3 SHEETS'SHEET 3 ZgWTI||llllllllllllllllmllllllml v Patented Dec. 19, 1922.

'J STATES HENRY B. TOI-IMS, OF CHICAGO, ILLINOIS.

VACUUM CYLINDER FOR PULP AND PAPER. MILLS.

Application filed June 30,

T 0 all whom it may concern:

Be it known that I, HENRY B. TOHMS, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain'new and useful Improvements in Vacuum Cylinders for Pulp and Paper Mills, of which the following is a specification.

My invention relates to improvements in means for extracting water or moisture from paper pulp stock or pulp sheets in the process of making paper.

One of the objects of the invention is to provide more reliable and eflicient means for extracting moisture from pulp web from which sheets of paper are subsequently to be made, during the traverse of the web.

The device is so arranged that excessive resistance to movement is not imposed upon the web during the time when moisture is being drawn therefrom.

My device is substantially an accessory for a machine which produces machine made paper. Briefly, such paper making machines consist in part of an endless wire cloth or belt, which travels from the breast roll to the couch rolls over a table consisting of small rolls, or the like. The liquid pulp is kept from flowing overv the edges of the wire by rubber straps or pulleys called deckels. The wire belt, in addition to the forward motion, has usually a lateral shake for the purpose of including the fibrous felt to knit together. As the wire belt moves forward, much of the water in the pulp leaches thru its meshes and is caught by a vacuum chest or box, to be returned again to help dilute the first pulp. Before the fibers reach the end of the deckels they pass over one or more suction boxes, which removes more or less water and leaves the web dry enough to maintain its position on the wire belt as it passes under the dandy roll.

In such machines the pulp and wire cloth belt then pass between the couch rolls, the top couch being covered with felt while the wire belt returns around the lower couch to the breast roll.

In accordance with my improvement the pulp sheet or web leaves the couch roll and passes around my vacuumcylinder, where- 1919. Serial No. 307,613.

by more moisture is extracted from the moving sheet. In passing around the vacuum cylinder is, preferably, contained between a conveylng belt and a strip of felt, the felt being, preferably, between the traveling web and the foraminous peripheral surface of my improved cylinder. After leavmg my improved cylinder the web, now devoid of a large part of its moisture, passes between pressure rolls, together with the felt which conveys it, and thru the further ordinary steps in the process of making paper, or the like.

In the accompanying drawings forming a part hereof:

Fig. 1 is an end elevation showing parts in section of my improved vacuum cylinder.

Fig. 2 is a section thereof taken on line 2-2 of Fig. 1.

Fig. 3 is a schematic view showing anair exhausting means and its manner of connection to the hollow shaft of the cylinder.

Fig. 4 is a section taken on line 44 of Fig. 1.

' Fig. 5 is a broken away part showing the peripheral wall before the wire cloth is secured thereto.

Fig. 6 is a section of an automatic valve for connecting the chambers to be exhausted with the exhausting means.

Fig. 7 is a plan view of one side of the valve.

Fig. 8 is a diagrammatic view of the wheel and associated devices.

In all the views the same reference characters areemployed to indicate similar parts.

In the exemplified embodiment of my invention, 10 indicates the cylinder or hollow roll, having a circuinferentially extending chamber 11, divided, at intervals, by radially extending imperforate partitions 12, to. provide vacuum chambers 13, between adjacent partiti ons. Each of the partitions 12 has its outer end, preferably, tapered, as at 14., and each partition 12 bears upon its sharp salient end a series of uniformly, spaced apart, transversely extending grooves 15, to receive spaced apart wires 16 that are wound about the wheel, Each wire may be a complete hoop. within itself. or it may be a convolution of a continuous spirally progressive wire. The object of the wire 16 is to form a support for an overlying fine mesh wire cloth 17. After the wires 16 have been placed around the wheel, substantially as shown in Fig. 5, the space between each Wire and the respective grooves 15 is filled in with solder, or other suitable material, to provide a continuous unbroken surface transversely extending at the apex of the tapered portion 14, as at 18.

The annular chamber is made up of a troughelike rim ortion having an inner wall 20 and side walls 21 and 22, each of which walls forms one leg of an angular ring having a laterally extending leg or member 23. The outer surface of the legs or members 23 is in substantially the same horizontal plane as the wire fabric 17 that covers the spaced apart wires 16 on the periphery of the cylinder. A hollow shaft 27 has hearings in pillow. blocks 28, at either end, supported upon standards 29. The hollow shaft 28 terminates, near one of the pillow blocks 28 in an enlarged hollow head 30, from which radiates a series of conduits or pipes 31, and which communicate with the interior of the head 30 and with respective vacuum chambers 11 contained between the adjacent partitions 12. At the inner edge of the circumferentially extending inner wall 20, between each pair of par-- titions 12, is a hollow bored out rib or bead 32, having openings 33 connecting it withv the respective vacuum chambers. In the end of each of these hollow rib portions. an elbow 34 is secured. to which the pipe 31 is connected. and between the pipe 31 and the pipe 35 is a normally closed VHlXB 36. In Fig. 2 this sort of valve is shown to be of the gate valve type in which a sliding plate 37 is held by a spring 38 that surrounds a stem 39 connected to the plate to hold the port 40, of the gate 37, out of register with the interior of the pipes 31 and 35. so that by this means the respective chambers 11 are effectively cut off from the interior of the hollow pipe 27. On the extended end of the stem 39 is a head 41 which normally bears against the relatively stationary annular and sinuous cam 42, which is fixed to the adjacent pillow block 28, as by means of set screws 43. The arrangement of the cam 42 is such that the stem 39 of the valve is pressed inwardly so that the port 40 of the valve, upon the rotation of the wheel, will, at a certain part of its revolution, be caused to register with the interior of the aligning pipes 31 and 35, whereby to connect the respective vacuum chamber lljwith the interior of the head 30, located at one end of the hollow pipe 27, so that during the rotation of the wheel, the chambers 11, will, successively, be thus automatically brought into communication with the hollow pipe 27, in which the air is attenuated.

The wheel is supported upon its axis by a plural arm spider 45, consisting of a central hub 16 and having radial arms 47 connected to the inner wall 20, at intervals, as at 4:8. There is preferably supported on the hollow shaft 27 a spider of this character, at each end. For the sake of clearness, it is not shown in Fig. 2, but is clearly defined in Fig. l.

The central shaft, which is rotatable in the pillow blocks 28, is connected to a vacuum pump 49, diagrammatically shown in Fig. 3, said pump being operated by a rotatable shaft 50, propelled by any suitable power, the pump being connected to the end of the shaft 27 by pipe 51 and by a suitable means 52, which permits the rotation of the shaft 27 without requiring rotation .of the pipe and yet there is maintained between the shaft 27 and the pipe 53 a substantially air tight joint effected by the cap 54 and the packing 55, or by any other suitable means or arrangement.

In the diagram disclosed in Fig. 8, I have shown my improved cylinder or wheel 10 in the position it would, preferably, occupy in conjunction with the usual paper making machine, in which 56,;tlie' usual wire cloth belt comes from the breast :rolland passes over the vacuum. or'suction boxes 57, 58 and 59, under the felt covered deckel roll 60 and under theusual dandy roll 61. The strip or pulp web 62 now passes downwardly in contact ivith the'outer surface of a continuously moved strip or belt of felt, 63. This strip or belt of felt, passes immediately into contact with the wire mesh 17 on the outer periphery of the cylinder, and over a series of pulleys 64:, 65 and 66. A conveying belt 67 passes over the top of a direction pulley 68 and then partly around a similar pulley or roll 69 and then into contact with the outer surface of the web strip or stock, as it passes around the vacuum cylinder. and over the pulley or roll 70. and thence under and partly around the pulley or roll 71. and

with the strip of substantially dehydrated fiber. of which the paper is to be made. passes thru the pressure rolls 72 and 73, and from this point passes thru the other neces sary steps required for finishing the products. After the paper or strip of pul of fibrous material leaves the dandy roll. it passes over the top of the couch roll 74.

Deckel belts 75 and 76 pass around the flanges 23 and 26. respectively, of the cylinder and over smaller pulleys 77 and 78, respectively. on the shaft. 80. These belts. 75 and 76 are impervious and are adapted to be moved laterally over suitable portions of the wire cloth 17, in the event that the pulp sheet is narrower than the entire width of the pervious portion of the cylinder. The belts 75 and 76 are moved laterally, toward and fromcach other, for

this purpose, by means of levers 81 and 82. Each of the levers 81 and 82 is pivoted, as at 83, to a suitable support 84. It has a shorter arm 85 which is bifurcated at its ends to provide two spaced apart members 86 which are slotted, as at 87. In the slots of each of these arm members is a pin 88, projecting from a sleeve 89 that is loose on the shaft 80 and slidable thereon by means of the levers 8182. The sleeve 89 is connected to the respective pulleys 77 and 7 8 in such manner that the axial movement of the sleeve, along the shaft 80, will move the pulleys 77 and 78, as the case may be, in accordance therewith, but the connection of the sleeve to the pulley does not impede the rotation of the pulley inthe slightest degree.

Now when the cylinder 10 is rotating and the levers 81 and 82, or either of them, is moved outwardly from the machine, they thus move the deckel belts 75 and 7 6 towards each other to cover more or less of the peripheral reticulate surface provided by the wire fabric 17. The limit of movement of the deckel belts, 75 and 76, is effected whenthey strike the collars 90 and 91 fixed to the shaft 80. cres cent shaped arms 92 are-fixed to the support 84 and provide spaced apart perforations 93, within which the pins 94 may be placed, which also pass thru the longer arm 81 of the lever. By this means the deckel belt pulley 77 or 7 8- is held in selected position,-

so that more or less of the reticulate peripheral surface of the cylinder may be covered by the overlying deckel belt.

As the vacuum cylinder 10 is rotated, the valve 36 communicating with several of the vacuum spaces or chambers 11, are pressed inwardly by a selected part of the cam 42,

as shown in Fig. 2-, thereby causing communication between the respective vacuum chambers and the interior of the hollow shaft 27. This will immediately attenuate the air that is within the' chamber so 45 connected, and cause a suction effect to draw the water, from the paper strip 62, thru the'underlying strip of felt 63 into the interior of the head 30 of the rotating hollow shaft 27. So soon as the. heads of the valves v41 pass .off of that portion of the cam 42 I that is nearest situated to the valves in their rotation, the spring 38 of the valve will automatically close the pipes 31 and 35, communicating with the vacuum chambers in the upper portion of the cylinder and prevent the air from being drawn thru them bythe suction effect of the exhaust pump I 49, and thus, the chambers underlying thestrip of felt only are active, for the pur-. pose of drawing water therefrom by the tendency of producing a vacuum in the selected number of underlying chambers of the cylinder.

While I have herein shown a single embodiment of my invention, for the purpose of clear disclosure, it will be manifest to persons skilled in the art, that many changes maybe made in the configuration and the general arrangement of the parts within the scope of the appended claims. 5

Having described my invention, what I claim is:

1. A device of the character described having in combinative association a rotatable, annular casing divided into a series of chambers, each chamber having a foraminous peripheral wall; air exhausting means effective to exhaust the chambers in consecutive order while in a predetermined region, within the path of the respective chambers, valves to connect the chambers with the exhausting means; a cam in the path of the valves to open them consecutively, means to hold a pervious sheet over the foraminous wall of the exhausted chamber, whereby to extract moisture therefrom; and a belt of impervious material operative to adjustably limit the effectivelateral extent of the foraminous wall to the width of the said pervious sheet.

2. A device of the character described having in combinative association a rotatable cylinder provided with an annular casing divided into a series of chambers, each chamber having a foraminous peripheral wall; air'exhausting means effective to substantially exhaust the chambers, in consecu tive order, while in a predetermined region within the path of the respective chambers; means to hold a pervious sheet over the foraminous wall of the exhausted chambers whereby to extract moisture therefrom and means to effectively reduce the lateral extent of the foraminous wall, while the chambers are in said zone, to compensate for the varying width of the sheets.

3. A device of the character described havin in combinative association a rotatable cylinder, provided with an annular casing divided into a series of chambers, each chamber having a foraminous peripheral wall; means to adjustably limit the effective width of the foraminous wall between predetermined dimensions; a hollow shaft upon which said cylinder is mounted; a. conduit, connecting each chamber to the hollow shaft; a normally closed valve in each conduit; means for exhausting the chambers, connected to said shaft, and a cam, in the rotative path of said valves to open them consecutively, whereb to effect communicationbetween said hol ow shaft and the respective chambers at predetermined zones within the path of rotation of said chambers.

4:. A device of the character described combinative association, a casing, wit a foraminous peripheral wall and a series of circumferentially consecutive chambers, between said wall and the axis of the cylinder;

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valves to exhaust said chambers consecutively, in predetermined zones in their path of rotative movement; a cam for opening said valves; a travelling belt of felt, or the like, overlying said perforate wall; another belt, partially surrounding said cylinder for holding a web of paper about the cylinder and in contact with said belt of felt and a pair of impervious belts partially encircling each end of the cylinder and adjustably mounted so that their inner edges are in close contact with the edges of the web of paper.

5. A device of the character described comprising a rotatable cylinder having in combinative association a casing, with a foraminous, peripheral wall and a series of circumferentially consecutive chambers, between said wall and the axis of the cylinder;

valves to exhaust certain of said chambers,

consecutively, in predetermined zones in their path of rotative movement; a cam in the path of the valves to open them consecutively; means to maintain the remaining valves closed; a travelling belt of felt.or the like, overlying the said perforate wall, near where the chambers are open; another belt, moving at substantially the same speed and surrounding that part of the said cylinder containing the open chambers, for holding a web of paper about that portion of the cylinder and in intimate contact with said belt of felt; means for reducing the effective lateral extent of the foraminous wall to the width of said overlying web of paper, said means comprising a pair of impervious belts partially encircling each end of the cy1inder and having their inner edges in close contact with the edges of the web of paper; and a. pair of pulleys actuating the impervious belts, said pulleys being slidably mounted on a rotatable shaft whereby said impervious belts are adjustable to webs of paper of varying widths.

6. A device of the character described comprising a rotatable cylinder having in combinative association acasing, with a foraminous peripheral wall and a series of circumferentially consecutive chambers, between said wall and the axis of the cylinder; means, to exhaust certain of said chambers, consecutively, at predetermined zones in their path of rotative movement; means to maintain the remaining chambers closed; an imperforate belt surrounding that portion of the cylinderwherein the chambers are open and means to move the belt laterally to cover more or less of the perforate peripheral wall of said chambers to accommodate webs of paper of varying widths.

' 7. A device of the character described comprising a rotatable cylinder having in combinative association a casing, with a foraminous peripheral wall and a series of circumferentially consecutive chambers between said wall and the axis of the cylinder; means to exhaust certain of said chambers, consecutively, at predetermined zones in their path of rotative movement; means to maintain the remaining chambers closed; an imperforate belt, one on each side of said cylinder and surrounding that portion of the cylinder wherein the chambers are open; means to move the belts laterally toward and from each other to cover more or less of the perforate peripheral walls of said chambers and means to holda web of paper about that portion of the cylinder in which the chambers are being exhausted.

In testimony whereof I hereunto subscribe my name.

HENRY B. TOHMS. 

